Automatic-spark control



June 19, 1928. 1,674,152

A. 0. ANDREW AUTOMATIC SPARK CONTROL Filed March 30, 1926 AT OJIndreM Patented June 19, 1928.

ARTHUR 0. ANDREW, OF LEON, IOWA.

I AUTOMATIC-SPARK CONTROL.

Application filed March 30,1926. Serial No. 98,585.

This invention relates to an improved automatic spark 'controlfor internal combus- "t on engines, being especially, although not exclusively, designedforuse in connection fiwith the engines ofFord motor vehicles,

and seeks, among other objects, to embody lmeans in the'commutator of such an engine "for automatically advancing and retarding "theignitioh as the speed of the engine is inqcreasedjordecreased. The invention seeks, as a further ob ect,

to' provide an improved'commutator brush "embodying a weighted lever and articulated "Contact" lever peculiarly ,"constructed and 'assembledin such manner that, as the speed ofthe engine is'increa'sed, the weighted lever *willfun'ction toangularly advance the contact'leverand consequently the instant of firing, while, as thespeed of the eng'ineis 'decreased, the weighted lever will be retracted forretarding the instant offiring.

A further objectof'the invention is to provide a brush wherein a single-spring will be 'utilizedzfor the .dual' purpose of retracting -the weighted leverand maintaining a tension-onthe contact lever tending to press the contact roller of the latter lever into engagement with thefixed contacts of the commutator shell, and wherein means will'be spring.

' And the invention seeks, as a still further object,to "provide a brush which will. be simple and sturdy in its construction and which may be readily applied without 'the necessity for structural change'in the enine. I Other objects of theinvention not specifically mentioned in the foregoing, will approvidedyfo1* adjustably tensioning said In the accompanying drawings:

Figure I-is a rear elevation showing my improved spark control in conjunction with a conven.tional commutator shell and timer shaft.- I

Figure 2 is a fragmentary plan view of the: brush employed. J

Figure3 is a sectional view of the support ing arm, and particularly showing the stop finger carried thereby. Y c

Figure 4-, is a detail sectional view of the weighted lever. i a t Figure 5 "is a plan view of the weighted l wg i l L:

pearduring the course of the following'de scription. i

Figure 6 is a plan view of the contact lever.

Referring now more particularly to the drawings, I have conventionally shown the timer shaft of a F ord engine at 10 and the usual commutator shell at 11; Fixed in the shell isfthe customary annular race 12, of suitable insulating material, and embedded in said race are quadrant-1y spaced segmental contacts 13 having terminals 14 to'which the circuit wiresare connected. Projecting from the shell is a lug l5, and the customary control rod (not shown) is attached to this lug forrotating the shell and advancing or retarding the instant of firing. As is well known, it is necessary to thus rotatably adjust the shell manually, with the result that the adjustment thereof is, often forgotten or neglected. Consequently, in starting the engine, backfiring not infrequently results while, in climbing grades, the engine is caused to pound. The presentinvention accordingly seeks to eliminate these abuses.

In carrying the invention into effect, I employ a sleeve 16'which isformed to lit over the timer shaft 10, and projecting from said sleeve is a radial arm 17. the forward'side of said arm near its outer end, as seen in Figure "3, is a rearwardly curved stop finger 18 which extends over the outer end of the arm, and formed on the arm at the base of said finger is a lateral lug 19. As shown in Figure 2, the sleeve 16 1s inotched to receive the usual locking pin 20,

and fitting over theforward end of the shaft 10 is the customary cap .41 overlying said pin, the can being held in position by the usual nut 22. Thus, as will be seen, the sleeve may be readily applied to the shaft.

Pivoted at one end upon the free end of the arm 17 is a substantially U-shaped weighted lever 23. 'Atsaid end thereof the lever is provided 'with lugs 2% which straddle the arm, and extending through said lugs and through the arm is a pivot pin 25 swingingly connecting the lever with the arm. As will be'obs erved, the stop finger 18 extends over the inner end of the lever in close spaced relationthereto to coact, at its free end, with the outer side of the lever;

At' its free end, the lever 23 is provided with lugs 26 similar to the lugs 24, and pivoted betweenthe former lugs is a contact lever 27. Asshown Figure 6, this lever is slit near its inner endalong parallel lines Formed on a I of the lever 23 is a pivot pin 29 swingingly connecting the levers with each other, the lever 27 being preferably formed of suitable resilient sheet metal. At its free outer end, the lever 27 is curved rearwardly, and journaled thereon is a contact roller to engage the inner periphery of the raceway 12 and cooperate with the contacts 13 of the commutator shell 11.

Secured atone end to the inner end of the lever 27 is a spring 31, and engaged with the opposite end of said spring is an anchoring screw 32' which is screwed through the lug 19 oft-he arm 17 and carries a lock nut 33. 7

Thus, as will be seen, the spring will tend to swing the outer end of the lever 27 outwardly and press the contact roller 30 into engagement with the raceway 12 so that said roller will, at all times, be held tightly in contact with the raceway to cooperate with the contacts 13. At the. same time, the

' spring 31 will, as will be seen, act on the lever 27 for swinging the free end of the weighted lever 23 inwardly and, as shown in Figure 1, normally holding the weighted lever close about the sleeve 16. i

As will now heseen, the weighted-lever 23 will, as the shaft 10 revolves, he swung out wardly by centrifugal force for advancing the lever 2? about the axis of said shaft and accordingly advancing the instant of firing.-

As thespeed of the timer shaft is increased,

' the lever 23 will, of course, be further swung Y. outwardly so that the instant of firing'will be advanced with the increasing speed of the timer-shaft until the lever 23 strikes the stop finger 18, when further outward movement of said lever will be limited by the finger.

'Conversely, as the speed of the timer shaft vis decreased, the spring 31 will function to retract the lever 23 so that the lever 27 will, in turn, be retracted with respect to the axis .of said shaft for retarding the instant of firing. 1 Thus, the lnechanism' will automatically function to control the instant of firing 7 with the speed of the engine and, of course,

the screw 32 may be adjustedfor varying the tension of the spring 31 and regulating the movement of the'weighted' lever Having thus described the invention, what Iclaim is: V v

1. A-commutator brushincluding an ele- .ment adapted for attachment to a timer shaft, a weighted centrifugal lever carried by said element, a contact lever pivoted between its ends upon the weighted lever with its contact end at the outer side of the weighted lever, the weighted lever being he,-

tweensaid contact endand the timer shaft,

I and means tending to move the contact lever 1 independently to active contact engaging position and normally holding said weighted lever retracted toward the timer shaft.

shaft, a weighted centrifugal lever carried by said element, a contact lever pivoted to the weighted lever for independent movement but movable with the weighted lever for advancing the instant of ignition, the contact lever extending rearwardly fromvits pivot at the outer side of the weighted lever, and a single yi'eldable means pulling constantly upon the contact lever to move the contact lever'independentlyto active contact engaging position and normally holding said weighted lever retractedtoward the timer shaft. I

3. A commutator brush including an element adapted for attachment to a timer shaft, a weighted centrifugal lever carried by said element, a contact lever pivoted be tween its ends at the free end of the weighted lever for independent movement but movable therewith for'advancing the instant of ignition, the working end of the pivotat the outer side of the weighted lever between said lever and the contactiraceway, and a spring connected to the'opposite' end of the contactlever and to the elemnt on the timer shaft to move the contact lever in dependently, to active contact engaging position' and normallyholding said weighted lever retracted. i H Ur f r 4; A commutator brush including an ele -:ment adapted for attachment to a timer shaft, a weighted centrifugal lever fulcrumed at oneend on said elementya contact lever pivoted upon'the weighted :lever for independent movement. but movable therewith for advancing the instant=ofigni'-' tion, the contact lever extending rearwardly from its pivot "at the outer side of the weighted lever, a'spring extendingbetween the contact lever and said element to move a the contact lever independently to active contact engaging "position and normally holding said weighted lever retracted, and a stop extending from said element at the outer side'of the weighted lever adjacent the fulcrumed end. thereof for limiting the weighted lever in its movement by centrifugal force.

5. A commutator brush including a sleeve adapted for attachment to'a timer shaft and provided with a' lateral arm, a weighted lever pivoted near one end upon said arm, a contactlever pivotedupon the free end portion of the weighted leverand movable there.

with for advancing the instant of ignition, 7

said lateral arm, ofthe sleeve at'the outer ugal lever, and means constantly pulling on the contact lever to swing the same to active 10 contact-engaging position and to hold the centrifugal lever agalnst centrifugal act1on.

In testimony whereof I affix my signature.

ARTHUR 0. ANDREW. [1 5.] 

